IT’S my 30th today. I’ve been feeling pretty good about kissing my twenties – a decade of enormous personal flux – goodbye. But it’s also the first time in a woman’s life when she’s really asked to think about aging. It’s a moment to take stock and ask what you’re doing with your life. It’s also time to employ a noise filter to attenuate for the many overt and covert messages about hitting this milestone. No more short skirts. Not married? Buy a cat or five. Oh – and your eggs are spoiling.

Since I spend a lot of time writing about these sorts of messages, I thought I’d nurtured a healthy critical distance from them. But three days ago, I sat in my little Corsa, put some Amy Winehouse on, and promptly started to sob instead of drive. I felt overwhelmed. My life in no way resembled the one I expected to have at this point.

I’m assured this is a fairly universal reaction. Lots of women I admire and respect admitted having their own wobble. It’s no wonder we take it badly when the overwhelming majority of the messages we receive about ageing as women are negative.

As my birthday crept closer, I’ve been fielding the usual tongue-in-cheek enquiries and comments. “How does it feel to be old?”, “It’s all downhill from here”, “You don’t look a day over 21”. Of course, there have been many assurances that the thirties are brilliant – more sense and more money for most – which mustn’t be sniffed at. Though this number, the comments and my children’s charming tendency to catalogue every grey hair, has meant facing the inescapable. I’m getting older.

Of course, 30 is nothing in the grand scheme of an average life. With medical advancements, my generation might be the first to regularly hit our centenary. But for women, things are different. Thirty is not just a third of the way through a life – it’s two-thirds through a life of social relevance. Women have a latent superpower: they reach 45 and magically disappear from view.

It’s hard not to internalise society’s ageist dictum. That our worth as women is in our reproductive value, signalled by youth and beauty. It’s easily believed thanks to the coloniality of youth in our culture, where women are both literally and figuratively airbrushed out. Ageing women’s bodies are absented from view, through plastic surgery, beauty treatments, diets, reduced airtime and more.

It’s cemented by the fallout of the increasing porn culture, where the youngest of viable women are preferred. The same goes for fashion, where young, often prepubescent-looking models are chosen. In Hollywood, Maggie Gyllenhaal was “too old” to play a 55-year-old’s wife whilst still in her thirties. Collectively, our gaze is pointed towards youth. Anything else is not a parallel norm, but a deviation.

When older women are permitted a role, it’s usually a one-dimensional stereotype. Comedy foil. A menopausal hysteric. Where are the older women carrying their own stories? Unless you’re Meryl Streep or Helen Mirren, and you’ve somehow managed to transcend the stereotyping. We better start work towards winning all those awards if we want to be valued as we age.

As we pass these temporal milestones – 30, 40, 50, 60 – we reflect on what messages we’re told about the ageing woman. Messages where age becomes shorthand for a litany of assumptions: unattractive, dithering, ill, tired, non-sexual, worthless. We imagine ourselves caught in the magazines’ red circle of shame, the cultural crosshairs that zero in on our increasing perceived imperfections. The older woman is a marginalised demographic, subject to the vice-like grip of misogyny and ageism.

We’ve had a very public display of this over the last year. The treatment of Hillary Clinton during the 2017 US election mirrors the deeply held prejudices embedded in society. She was mocked for her health, called a Golden Girl, and regularly referred to as a grandma – as if knitting and cookies are more fitting for her than pursuing the presidency. Even though she’s two years Trump’s junior.

That’s how rooted the idea of women’s lesser intellectual value still is. We’re not expected to use our minds like men. The natural conclusion of this is that wisdom – the maturation of knowledge and experience – is viewed as a masculine trait.

When men’s looks fade, they have their brains and experience to rely on for respect. They have a third-age value women do not, because society instils them with intellectual value from an early age.

This is why when our looks disappear, we’re seen as worthless. This is the pseudospeciation of older woman. With age, we slip out of view.

My mother, in her mid fifties, is experiencing her own version. Though more qualified and experienced than younger candidates, finding a new job is more difficult than ever. Her experience is backed up by research from the US’s National Bureau of Economic Research. Women over 45 were called back less frequently, offered less money and hired less. As women generally live longer than men, this can significantly impact their life chances.

In Scotland we have an ageing population. Households headed by over 65s will increase by 54 per cent between 2012 and 2037. Here, we simply cannot afford to push older women to the margins of society.

In pre-patriarchal societies the elder woman was revered, cutting across cultures. Hestia. Hera. Kali. In paganism, the triple goddess was worshipped as the Maiden, Mother and Crone, each symbolising a distinct phase of a woman’s life. In Native American cultures, the grandmothers are evoked as symbols of comfort and strength.

How did older women lose their value? It’s a question we need to ask ourselves.